penitentiary

a place for imprisonment, reformatory discipline, or punishment, especially a prison maintained in the U.S. by a state or the federal government for serious offenders.

2.

Roman Catholic Church. a tribunal in the Curia Romana, presided over by a cardinal (grand penitentiary) having jurisdiction over certain matters, as penance, confession, dispensation, absolution, and impediments, and dealing with questions of conscience reserved for the Holy See.

early 15c., "place of punishment for offenses against the church," from Medieval Latin penitentiaria, from fem. of penitentiarius (adj.) "of penance," from Latin paenitentia "penitence" (see penitence). Meaning "house of correction" (originally an asylum for prostitutes) is from 1806, short for penitentiary house (1776). Slang shortening pen is attested from 1884.